Links for Keyword: Brain imaging

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By Arianne Cohen1 minute Read You know all those studies about brain activity? The ones that reveal thought patterns and feelings as a person performs a task? There’s a problem: The measurement they’re based on is inaccurate, according to a study out of Duke University that is rocking the field. Functional MRI machines (fMRIs) are excellent at determining the brain structures involved in a task. For example, a study asking 50 people to count or remember names while undergoing an fMRI scan would accurately identify which parts of the brain are active during the task. Brain scans showing functional MRI mapping for three tasks across two different days. Warm colors show the high consistency of activation levels across a group of people. Cool colors represent how poorly unique patterns of activity can be reliably measured in individuals. View image larger here. [Image: Annchen Knodt/Duke University] The trouble is that when the same person is asked to do the same tasks weeks or months apart, the results vary wildly. This is likely because fMRIs don’t actually measure brain activity directly: They measure blood flow to regions of the brain, which is used as a proxy for brain activity because neurons in those regions are presumably more active. Blood flow levels, apparently, change. “The correlation between one scan and a second is not even fair, it’s poor,” says lead author Ahmad Hariri, a professor of neuroscience and psychology at Duke University. The researchers reexamined 56 peer-reviewed, published papers that conducted 90 fMRI experiments, some by leaders in the field, and also looked at the results of so-called “test/retest” fMRIs, where 65 subjects were asked to do the same tasks months apart. They found that of seven measures of brain function, none had consistent readings.

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27339 - Posted: 07.01.2020

The Human Brain Project (HBP) has announced the start of its final phase as an EU-funded FET Flagship. The European Commission has signed a grant agreement to fund the HBP with 150 million Euros from now until 2023. Over the next three years, the project will narrow its focus to advance three core scientific areas – brain networks, their role in consciousness, and artificial neural nets – while expanding its innovative EBRAINS infrastructure. EBRAINS offers the most comprehensive atlas and database on the human brain, directly coupled with powerful computing and simulation tools, to research communities around neuroscience, medicine and technology. Currently transitioning into a sustainable infrastructure, EBRAINS will remain available to the scientific community, as a lasting contribution of the HBP to global scientific progress. Supercomputers, Big Data Analytics, Simulation, Robots and AI have all become new additions to the “toolbox” of modern neuroscience – a development strongly pushed forward by the HBP and its EBRAINS infrastructure. Started in 2013 as a FET Flagship project, the HBP is the largest brain science project in Europe. Now entering the final phase of its ten-year lifespan, the project is proud to present its scientific workplan and transformative technological offerings for brain research and brain-inspired research and development. HBP’s scientific activities in the new phase focus on three topics: networks that are studied across different spatial and temporal scales, their significance for consciousness and disorders of consciousness, and the development of artificial neural networks and neurorobotics.

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27337 - Posted: 07.01.2020

Published by Steven Novella under Neuroscience This is an important and sobering study, that I fear will not get a lot of press attention – especially in the context of current events. It is a bit wonky, but this is exactly the level of knowledge one needs in order to be able to have any chance of consuming and putting into context scientific research. I have discussed fMRI previously – it stands for functional magnetic resonance imaging. It uses MRI technology to image blood flow to different parts of the brain, and from that infer brain activity. It is used more in research than clinically, but it does have some clinical application – if, for example, we want to see how active a lesion in the brain is. In research it is used to help map the brain, to image how different parts of the brain network and function together. It is also used to see which part of the brain lights up when subjects engage in specific tasks. It is this last application of fMRI that was studied. Professor Ahmad Hariri from Duke University just published a reanalysis of the last 15 years of his own research, calling into question its validity. Any time someone points out that an entire field of research might have some fatal problems, it is reason for concern. But I do have to point out the obvious silver lining here – this is the power of science, self-correction. This is a dramatic example, with a researcher questioning his own research, and not afraid to publish a study which might wipe out the last 15 years of his own research. Copyright © 2020 All Rights Reserved .

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27288 - Posted: 06.08.2020

Hundreds of published studies over the last decade have claimed it's possible to predict an individual’s patterns of thoughts and feelings by scanning their brain in an MRI machine as they perform some mental tasks. But a new analysis by some of the researchers who have done the most work in this area finds that those measurements are highly suspect when it comes to drawing conclusions about any individual person’s brain. Watching the brain through a functional MRI machine (fMRI) is still great for finding the general brain structures involved in a given task across a group of people, said Ahmad Hariri, a professor of psychology and neuroscience at Duke University who led the reanalysis. “Scanning 50 people is going to accurately reveal what parts of the brain, on average, are more active during a mental task, like counting or remembering names,” Hariri said Functional MRI measures blood flow as a proxy for brain activity. It shows where blood is being sent in the brain, presumably because neurons in that area are more active during a mental task. The problem is that the level of activity for any given person probably won’t be the same twice, and a measure that changes every time it is collected cannot be applied to predict anyone’s future mental health or behavior. Hariri and his colleagues reexamined 56 published papers based on fMRI data to gauge their reliability across 90 experiments. Hariri said the researchers recognized that “the correlation between one scan and a second is not even fair, it’s poor.” © Copyright 2020 Duke University.

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27283 - Posted: 06.04.2020

by Chloe Williams / A new flexible electrode array can detect the activity of neurons in a rat’s brain at high resolution for more than a year1. The device could be used to study how neuronal activity is altered in autism. Arrays usually have wires connected to each electrode to pick up its signal, but this design is bulky and works only in arrays consisting of 100 electrodes or fewer, limiting the array’s coverage and resolution. Devices with thousands of electrodes have integrated switches to consolidate signals into fewer wires. But these devices usually have a lifespan of only a few days. Their polymer-based coatings are often permeable to water or contain tiny defects that allow body fluids to seep into the device and current to leak out, damaging both the device and brain tissue. The new device combines electronic switches and a specialized protective coating so that scientists can record activity at the surface of the brain at high resolution over extended periods of time. The array, called Neural Matrix, consists of 1,008 surface electrodes laid out in 28 columns and 36 rows. Switches, or transistors, built into the array combine signals from all the electrodes in a column to a single output wire. The signals from each electrode in the column are recorded via the wire in a specific sequence, making it possible to separate them later. © 2020 Simons Foundation

Related chapters from BN8e: Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27282 - Posted: 06.04.2020

By Dennis Normile Scientists studying brains and other organs and cancerous tumors have long tried to get detailed 3D views of their insides—down to the level of blood vessel and cell type. But producing such images is time-consuming and difficult. Now, dramatic improvements to a 3D imaging technique can reveal the internal components of entire organs or even animals in a simple procedure, researchers report this week. The new tissue staining protocol allows cellular level analyses in unprecedented detail; it could aid research efforts in neuroscience, developmental and evolutionary biology, and immunology, and it could prove useful in diagnosing some cancers and studying damaged brain tissue after death. To image biological samples in 3D, researchers basically have two main options: They can slice tissues into thin sections and use computer software to reconstruct the whole sample, or they can render biological tissue transparent using special chemicals, which lets researchers view its interior with an optical microscope. To distinguish different cell types, researchers typically stain tissues by soaking them in a cocktail of dyes and chemicals. But getting staining dyes to penetrate organs and large samples has proved difficult. To tackle this problem, researchers at the RIKEN Center for Biosystems Dynamics Research identified a gel that closely mimics the physicochemical properties of organs that have undergone the tissue clearing process. Starting with computer simulations and following up with laboratory tests, the team optimized the soaking solution temperature, dye and antibody concentrations, chemical additives, and electrical properties to produce the best staining and imaging results. They then tested their method with more than two dozen commonly used dyes and antibodies on mouse and marmoset brains. © 2020 American Association for the Advancement of Science.

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27227 - Posted: 05.02.2020

Ruth Williams Scientists have created a light-responsive opsin so sensitive that even when engineered into cells deep within tissue it can respond to an external light stimulus, according to a report in Neuron yesterday (April 30). Experiments in mice and macaques showed that shining blue light on the surface of the skull or brain was sufficient to activate opsin-expressing neurons six millimeters deep. “I was pretty blown away that this was even possible,” says Gregory Corder, who studies the neurological basis of pain and addiction at the University of Pennsylvania and who was not involved with the work. At that sort of depth, he continues, “essentially no part of the rodent brain is off-limits now for doing this non-invasive [technique]. . . . It’s pretty impressive.” “This development will help to extend the use of optogenetics in non-human primate models, and bring the techniques closer to clinical application in humans,” adds neurological disease expert Adriana Galvan of Yerkes National Primate Research Center in an email to The Scientist. Galvan was not a member of the research team. Optogenetics is a technique whereby excitable cells, such as neurons, can be controlled at will by light. To do this, cells are genetically engineered to produce ion channels called opsins that sit in the cells’ membranes and open in response to a certain wavelength of light. Switching on the light, then, floods the cells with ions, causing them to fire. Because light doesn’t penetrate tissue easily, to activate opsin-producing neurons deep in the brain of a living animal, researchers insert fiber optic cables. This is “highly invasive,” says Galvan, explaining that “the brain tissue can be damaged.” © 1986–2020 The Scientist.

Related chapters from BN8e: Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 27226 - Posted: 05.02.2020

Abby Olena Instead of a traditional lymphatic system, the brain harbors a so-called glymphatic system, a network of tunnels surrounding arteries and veins through which fluid enters and waste products drain from the brain. In a study published March 25 in Science Translational Medicine, researchers show that the rodent eye also has a glymphatic system that takes out the trash through spaces surrounding the veins within the optic nerve. They also found that this system may be compromised in glaucoma and is capable of clearing amyloid-β, the build up of which has been implicated in the development of Alzheimer’s disease, glaucoma, and age-related macular degeneration. The work began in the group of Maiken Nedergaard, a neuroscientist with labs at both the University of Rochester Medical School and the University of Copenhagen, who described the glymphatic system of the brain in 2012. Xiaowei Wang, then a graduate student in Nedergaard’s group and now a postdoc at the University of California, San Francisco, was interested in the eye and spearheaded the search for an ocular glymphatic system. At that point, nobody had speculated that the optic nerve—in addition to transmitting electrical signals—is also a fluid transport highway, Nedergaard says. As Wang’s project was getting underway, Nedergaard met Lu Chen, a neuroscientist at the University of California, Berkeley, at a meeting. Chen’s group had done previous research on ocular lymphatics that focused on the front of the eye. There, the majority of the aqueous humor—the fluid that fills the chamber between the cornea and the lens—drains from the eye to the surrounding vasculature through a circular lymph-like vessel called Schlemm’s canal. This helps regulate intraocular pressure. Chen tells The Scientist that she and Nedergaard decided to collaborate to connect the knowledge about the front of the eye with their questions about the back of the eye. © 1986–2020 The Scientist

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 7: Vision: From Eye to Brain
Link ID: 27207 - Posted: 04.22.2020

Gregory Berns, M.D., Ph.D. There is no official census for dogs and cats, but in 2016, the American Veterinary Medical Association estimated that 59 percent of households in the United States had a pet. Although the numbers of dogs and cats remains debatable, dogs continue to gain in popularity with 38 percent of households having at least one. Families with children are even more likely to have a dog (55 percent). With all due respect to cats, dogs have insinuated themselves into human society, forming deep emotional bonds with us and compelling us to feed and shelter them. Worldwide, the dog population is approaching one billion, the majority free-ranging. Even though many people are convinced they know what their dog is thinking, little is actually known about what is going on in dogs’ heads. This may be surprising because the field of experimental psychology had its birth with Pavlov and his salivating dogs. But as dogs gained traction as household pets, in many cases achieving the status of family members, their use as research subjects fell out of favor. In large part, this was a result of the Animal Welfare Act of 1966, which set standards for the treatment of animals in research and put an end to the practice of stealing pets for experimentation. How strange it is then that these creatures, whose nearest relatives are wolves, live with us and even share our beds, yet we know almost nothing about what they’re thinking. In the last decade or so, however, the situation has begun to change, and we are in the midst of a renaissance of canine cognitive science. Research labs have sprung up around the world, and dogs participate not as involuntary subjects, but as partners in scientific discovery. This new research is beginning to shed light on what it’s like to be a dog and the nature of the dog-human bond. © 2020 The Dana Foundation.

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27195 - Posted: 04.16.2020

Our ability to study networks within the nervous system has been limited by the tools available to observe large volumes of cells at once. An ultra-fast, 3D imaging technique called SCAPE microscopy, developed through the National Institutes of Health (NIH)’s Brain Research through Advancing Innovative Technologies (BRAIN) Initiative, allows a greater volume of tissue to be viewed in a way that is much less damaging to delicate networks of living cells. In a study published in Science, researchers used SCAPE to watch for the first time how the mouse olfactory epithelium — the part of the nervous system that directly perceives smells — reacted in real time to complex odors. They found that those nerve cells may play a larger and more complex role in interpreting smells than was previously understood. “This is an elegant demonstration of the power of BRAIN Initiative technologies to provide new insights into how the brain decodes information to produce sensations, thoughts, and actions,” said Edmund Talley, Ph.D., program director, National Institute of Neurological Disorders and Stroke (NINDS), a part of NIH. The SCAPE microscope was developed in the laboratory of Elizabeth M.C. Hillman, Ph.D., professor of biomedical engineering and radiology and principal investigator at Columbia’s Zuckerman Institute in New York City. “SCAPE microscopy has been incredibly enabling for studies where large volumes need to be observed at once and in real time,” said Dr. Hillman. “Because the cells and tissues can be left intact and visualized at high speeds in three dimensions, we are able to explore many new questions that could not be studied previously.”

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 9: Hearing, Balance, Taste, and Smell
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 6: Hearing, Balance, Taste, and Smell
Link ID: 27189 - Posted: 04.14.2020

By Robert Frederick An early sign of neurodegenerative disease at the cellular level is often the loss of integrity in axons, the threadlike part of neurons that conduct impulses. To find out what causes that loss of integrity, researchers have been trying to better understand the axon’s lining, called the membrane-associated periodic scaffold (MPS). If neuroscientists can discover what signals the MPS to disassemble, they may gain an early diagnostic tool for neurodegenerative diseases or a new target for drug therapy. Back in 2013, researchers using advanced optical microscopy identified the presence of rings in the MPS made from the protein actin. At first, the discovery was met with skepticism because no one had seen the rings using electron microscopes, which have more resolution than optical methods. But preparing neurons for electron microscopy often involves dissolving the membrane with a surfactant. “If you remove completely the membrane, you also disorganize the scaffold that is very tightly associated with the membrane,” says Christophe Leterrier, a neuro-biologist at Aix-Marseille Université in France. To see the periodic rings (shown above in orange at increasing levels of zoom) Leterrier combined optical and electron microscopy. Just as previous researchers had done to visualize the MPS, the first step involved a technique called unroofing a cell, which can isolate a cell’s membrane without disorganizing the underlying scaffold. But the researchers then used electron microscopy to image the same unroofed axon: Teamed up with Stéphane Vassilopoulos, Leterrier’s group essentially made a platinum replica of the MPS and used electron microscopy (shown above in grayscale) on the replica “to really see individual proteins.” The researchers published their findings in Nature Communications, discovering that the rings are like braided wreaths made from long actin filaments. Leterrier says the next step is to find what signal will prompt the MPS to disassemble but will not affect a neuron’s other actin structures, such as dendritic spines, which receive other neurons’ signals. © 2020 Sigma Xi, The Scientific Research Honor Society

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27159 - Posted: 04.02.2020

By Stephen Casper. The poet Emily Dickinson rendered the brain wider than the sky, deeper than the sea, and about the weight of God. Scientists facing the daunting task of describing this organ conventionally conjure up different kinds of metaphor — of governance; of maps, infrastructure networks and telecommunications; of machines, robots, computers and the Internet. The comparisons have been practical and abundant. Yet, perhaps because of their ubiquity, the metaphors we use to understand the brain often go unnoticed. We forget that they are descriptors, and see them instead as natural properties. Such hidden dangers are central to biologist and historian Matthew Cobb’s The Idea of the Brain. This ambitious intellectual history follows the changing understanding of the brain from antiquity to the present, mainly in Western thought. Cobb outlines a growing challenge to the usefulness of metaphor in directing and explaining neuroscience research. With refreshing humility, he contends that science is nowhere near working out what brains do and how — or even if anything is like them at all. Cobb shows how ideas about the brain have always been forged from the moral, philosophical and technological frameworks to hand for those crafting the dominant narratives of the time. In the seventeenth century, the French philosopher René Descartes imagined an animal brain acting through hydraulic mechanisms, while maintaining a view of the divine nature of a mind separate from matter. Later authorities, such as the eighteenth-century physician and philosopher Julien Offray de Le Mettrie, secularized the image and compared the human to a machine. The Italian physicist Alessandro Volta rejected the idea of ‘animal electricity’, proposed by his rival Luigi Galvani as a vital force that animates organic matter. Volta was driven at least partly by his aversion to the mechanistic view. © 2020 Springer Nature Limited

Related chapters from BN8e: Chapter 1: Introduction: Scope and Outlook; Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: An Introduction to Brain and Behavior; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27154 - Posted: 03.31.2020

Bob McDonald · CBC Radio Technology used to determine the structure of the Earth's interior using seismic waves has been adapted into a prototype brain scanner that could give results in real time. It could also be cheaper and simpler to use than technologies like MRI or CT scans. For decades, geologists have used sound waves travelling through the Earth, either from earthquakes or artificial sources, to search for oil, image fault lines and attempt to predict earthquakes. Reading reflections and refraction of the waves as they pass through different kinds of rocks and deposits can help geologists essentially do an ultrasound to build up a picture of the Earth. But in recent years seismology has been supercharged by a computational technique called full waveform inversion (FWI), which uses complex computer algorithms to scavenge ever more information from seismic data, and make much more detailed and accurate 3D maps of the Earth's crust. Now scientists at Imperial College London have adapted the same technology into a prototype head-mounted scanner that produced imaging information they say could be used in the future to produce high-resolution 3D images of the brain. The wavefield is shown as it propagates across the head. (Dr Lluís Guasch / Imperial College London / University College London / Nature Digital Medicine) The device uses a helmet fitted with an array of acoustic transducers that act as both sound transmitters and receivers. The system uses low frequency sound waves that are able to penetrate the skull and pass through the brain without harming brain tissue. The sound waves are altered as they pass through different brain structures, then the signals are read and run through the FWI algorithm. In simulations the team got results that make them confident they can produce high-resolution 3D images that may be as good, if not better, than more traditional approaches. ©2020 CBC/Radio-Canada.

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27122 - Posted: 03.16.2020

Ashley Yeager Genes that code for the structure and function of brain regions essential for learning, memory, and decision-making are beginning to be revealed, according to a report published last October in Nature Genetics. Analyzing MRI scans and blood samples from more than 38,000 individuals, as well as gene expression, methylation, and neuropathology of hundreds of postmortem brains, an international team of researchers identified 199 genes that affect the development of the brain, the connections and communication among nerve cells, and susceptibility to neurological disorders. New tools for studying neural tissue, such as RNA sequencing, have spurred a “very strong revival in studying human postmortem brains,” says Sabina Berretta, director of the Harvard Brain Tissue Resource Center at McLean Hospital in Boston. The Nature Genetics study and others like it have the potential to answer many questions about how the healthy brain functions, but they highlight one of the major challenges neuroscientists face right now—limited access to donated brain tissue, specifically from individuals unaffected by neurological disorders. While the Nature Genetics study included massive amounts of data from scans and blood, the researchers had gene expression data from only 508 postmortem brains. “We are really fortunate to get donations from people with a very large variety of dementias and other neurological disorders, such as Parkinson’s and Huntington’s disease,” Berretta says. “But we get very few donations from people that suffer from psychiatric disorders, schizophrenia, bipolar disorder, major depression, and anxiety, and [even fewer from] unaffected donors.” As a result, brain banks are reaching out to religious groups and also scientific communities not tied to any particular neurological condition to increase donations of healthy brains. © 1986–2020 The Scientist.

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27075 - Posted: 02.27.2020

Diana Kwon In the 16th century, when the study of human anatomy was still in its infancy, curious onlookers would gather in anatomical theaters to catch of a glimpse of public dissections of the dead. In the years since, scientists have carefully mapped the viscera, bones, muscles, nerves, and many other components of our bodies, such that a human corpse no longer holds that same sense of mystery that used to draw crowds. New discoveries in gross anatomy—the study of bodily structures at the macroscopic level—are now rare, and their significance is often overblown, says Paul Neumann, a professor who specializes in the history of medicine and anatomical nomenclature at Dalhousie University. “The important discoveries about anatomy, I think, are now coming from studies of tissues and cells.” Over the last decade, there have been a handful of discoveries that have helped overturn previous assumptions and revealed new insights into our anatomy. “What’s really interesting and exciting about almost all of the new studies is the illustration of the power of new [microscopy and imaging] technologies to give deeper insight,” says Tom Gillingwater, a professor of anatomy at the University of Edinburgh in the UK. “I would guess that many of these discoveries are the start, rather than the end, of a developing view of the human body.” © 1986–2020 The Scientist

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27058 - Posted: 02.20.2020

Blake Richards Despite billions of dollars spent and decades of research, computation in the human brain remains largely a mystery. Meanwhile, we have made great strides in the development of artificial neural networks, which are designed to loosely mimic how brains compute. We have learned a lot about the nature of neural computation from these artificial brains and it’s time to take what we’ve learned and apply it back to the biological ones. Neurological diseases are on the rise worldwide, making a better understanding of computation in the brain a pressing problem. Given the ability of modern artificial neural networks to solve complex problems, a framework for neuroscience guided by machine learning insights may unlock valuable secrets about our own brains and how they can malfunction. Our thoughts and behaviours are generated by computations that take place in our brains. To effectively treat neurological disorders that alter our thoughts and behaviours, like schizophrenia or depression, we likely have to understand how the computations in the brain go wrong. However, understanding neural computation has proven to be an immensely difficult challenge. When neuroscientists record activity in the brain, it is often indecipherable. In a paper published in Nature Neuroscience, my co-authors and I argue that the lessons we have learned from artificial neural networks can guide us down the right path of understanding the brain as a computational system rather than as a collection of indecipherable cells. © 2010–2020, The Conversation US, Inc.

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 13: Memory, Learning, and Development
Link ID: 27042 - Posted: 02.14.2020

By Pallab Ghosh Science correspondent, BBC News, Seattle US researchers are developing a better understanding of the human brain by studying tissue left over from surgery. They say that their research is more likely to lead to new treatments than studies based on mouse and rat models. Dr Ed Lein, who leads the initiative at the Allen Institute has set up a scheme with local doctors to study left over tissue just hours after surgery. He gave details at the American Association for the Advancement of Science meeting in Seattle. "It is a little bit crazy that we have such a huge field where we are trying to solve brain diseases and there is very little understanding of the human brain itself," said Dr Lein. "The field as a whole is largely assuming that the human brain is similar to those of animal models without ever testing that view. "But the mouse brain is a thousand times smaller, and any time people look, they find significant differences." Dr Lein and his colleagues at the Allen Institute in Seattle set up the scheme with local neurosurgeons to study brain tissue just hours after surgery - with the consent of the patient. It functions as if it is still inside the brain for up to 48 hours after it has been removed. So Dr Lein and his colleagues have to drop everything and often have to work through the night once they hear that brain tissue has become available. © 2020 BBC

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 27040 - Posted: 02.14.2020

By Kelly Servick Since its launch in 2013, the Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative has doled out about $1.3 billion in grants to develop tools that map and manipulate the brain. Until now, it has operated with no formal director. But last week, the National Institutes of Health (NIH), which manages the initiative and is a key funder, announced that neurobiologist John Ngai would take the helm starting in March. Ngai, whose lab at the University of California, Berkeley, focuses on the neural underpinnings of the sense of smell, has helped lead BRAIN-funded efforts to classify the brain’s dizzying array of cell types with RNA sequencing. Ngai told ScienceInsider about how the initiative is evolving and how he hopes to influence it. The interview has been edited for clarity and brevity. Q: Why is the BRAIN Initiative getting a director now? A: The initiative has been run day to day by a terrific team of senior program directors and staff with oversight from the 10 NIH institutes and centers that are involved in BRAIN. Walter Koroshetz [director of the National Institute of Neurological Disorders and Stroke] and Josh Gordon [director of the National Institute of Mental Health] have been overseeing the activities of BRAIN … kind of in addition to their “day jobs.” I think as enterprises emerge from their startup phase, which is typically the first 5 years, the question is how do you translate this into a sustainable enterprise, and yet maintain this cutting-edge innovation? … How do we leverage all the accomplishments that have been made, not just within BRAIN, but in molecular biology, in engineering, in chemistry and computer science, in data science. The initiative really will benefit from somebody thinking about this 24/7. © 2019 American Association for the Advancement of Science.

Related chapters from BN8e: Chapter 1: Introduction: Scope and Outlook; Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 1: An Introduction to Brain and Behavior; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 27020 - Posted: 02.05.2020

Abby Olena Understanding the array of neural signals that occur as an organism makes a decision is a challenge. To tackle it, the authors of a study published last week (January 16) in Cell imaged large swaths of the larval zebrafish brain as the animals decided which way to move their tails to avoid an undesirable situation. Finding patterns in the data, they were then able to use imaging to predict—10 seconds in advance—the timing and direction of the fish’s movement. “In a lot of other model systems it’s really difficult to actually . . . record something that’s happening throughout the whole brain with a high level of precision,” says Kristen Severi, a biologist at the New Jersey Institute of Technology who was not involved in the study. “When you have something like a larval zebrafish where you have access to the entire brain with single-cell resolution in a transparent vertebrate, it’s a great place to start to try to look for activity patterns that might be distributed and might be hard to connect.” Even if an animal has learned to do something, it doesn’t execute the exact same motor responses every time, says biophysicist Alipasha Vaziri of the Rockefeller University. He adds that common approaches to studying the neural basis of decision-making may not tell the whole story. For instance, monitoring a handful of neurons and then extrapolating from their activity what’s happening brain-wide means that researchers might miss the big picture. Likewise, recording across the whole brain and then averaging results across trials risks losing details essential to understanding how the brain encodes this behavior. © 1986–2020 The Scientist

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 5: The Sensorimotor System
Link ID: 26990 - Posted: 01.24.2020

Janelia and Google scientists have constructed the most complete map of the fly brain ever created, pinpointing millions of connections between 25,000 neurons. Now, a wiring diagram of the entire brain is within reach. In a darkened room in Ashburn, Virginia, rows of scientists sit at computer screens displaying vivid 3-D shapes. With a click of a mouse, they spin each shape to examine it from all sides. The scientists are working inside a concrete building at the Howard Hughes Medical Institute’s Janelia Research Campus, just off a street called Helix Drive. But their minds are somewhere else entirely – inside the brain of a fly. Each shape on the scientists’ screens represents part of a fruit fly neuron. These researchers and others at Janelia are tackling a goal that once seemed out of reach: outlining each of the fly brain’s roughly 100,000 neurons and pinpointing the millions of places they connect. Such a wiring diagram, or connectome, reveals the complete circuitry of different brain areas and how they're linked. The work could help unlock networks involved in memory formation, for example, or neural pathways that underlie movements. Gerry Rubin, vice president of HHMI and executive director of Janelia, has championed this project for more than a decade. It’s a necessary step in understanding how the brain works, he says. When the project began, Rubin estimated that with available methods, tracing the connections between every fly neuron by hand would take 250 people working for two decades – what he refers to as “a 5,000 person-year problem.”

Related chapters from BN8e: Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 26984 - Posted: 01.23.2020